1. Addition of trace elements to common and tartary buckwheat (Fagopyrum esculentum and F. tataricum)Mateja Germ, Nina Kacjan-Maršić, Helena Šircelj, Ana Kroflič, Ana Jerše, Vekoslava Stibilj, Drena Gadžo, Cheol Ho Park, Aleksandra Golob, 2020, pregledni znanstveni članek Povzetek: Plants need at least 14 elements for normal functioning. Selenium (Se) is on the list of beneficial elements for plants, since it has many positive effects in a propriate concentrations. Iodine (I) is not yet classified on that list since there are not enough studies about the effect of I on plants. Selenium in plants may cause a delay of senescence and promote the growth of the ageing seedlings. Selenium also exhibits protective role in UV treated plants, plants, exposed to water shortage, and in plants, exposed to high or low temperature. High concentration of Se was reported to cause physiological disturbances in plants due to Se binding to cysteine and methionine molecules instead of S, and the inclusion of selenocysteine and selenomethionine in proteins. I might have a positive effect on plants, including its protective role in antioxidant activities in plants, exposed to different stress conditions. Both elements are in deficit in human nutrition in many countries worldwide. I and Se are needed for the optimal function of thyroid gland, thus simultaneous biofortification of crops is feasible for areas deficient in both elements. Selenium and I interfere with each other in pea, common buckwheat plants and in kohlrabi. Sulphur (S) and Se have similar chemical properties, and the assimilation of Se and S follows the S metabolic pathway. S induced the accumulation of Se in Tartary buckwheat in field experiment. Silicon (Si) enhances plant strength, ameliorates the negative effects of salinity, drought, and high or low temperatures, ameliorates metal toxicity, and increases plant resistance to different pathogens and herbivores.
Ključne besede: buckwheat, Fagopyrum, selenium, iodine, sulphur, silicon
Objavljeno v DiRROS: 21.01.2026; Ogledov: 410; Prenosov: 287
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2. Differences in xylem and phloem structure in living stumps of Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.)Jožica Gričar, Miha Drolc, Peter Prislan, Helena Šircelj, 2025, izvirni znanstveni članek Povzetek: Living stumps reported in many tree species were the first, circumstantial evidence of root grafting. Although stump overgrowth has been extensively studied in various tree species, anatomical observations have mainly focused on the xylem part. Here, we investigated the xylem and phloem structure in living stumps of two conifer species: Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.). The mechanism of wound closure was similar in the two species, however, there were differences in the structure of wound tissues in wood and bark. Immediately after the injury, a callus consisting of parenchymal cells was formed, followed by wound-wood with wide increments. In addition, the wood structure and morphology of tracheids were changed. Tracheids lost their typical elongated and tapering structure; instead, numerous crooked and forked tracheids were present. Traumatic resin canals were present in both species but were more abundant in P. abies, which also had normal resin canals. While the structure of the xylem growth rings eventually normalized in both species, the width of the annual xylem increments was diminished. In both species, the typical structure of annual phloem increment was lost in the non-collapsed phloem and sclereids were very abundant in the collapsed phloem. In A. alba, the collapsed phloem was rich in swollen parenchyma cells containing blue-stained contents, while in P. abies, numerous large traumatic resin canals were conspicuous. The study showed that similar patterns of vascular tissue restoration exist in A. alba and P. abies in response to tree felling. However, there are certain species-specific peculiarities in the wood and phloem anatomical response, which might affect long-term stump functioning and survival.
Ključne besede: wood physiology, phloem, xylem, Norway spruce, Picea abies, silver fir, Abies alba
Objavljeno v DiRROS: 03.12.2024; Ogledov: 1177; Prenosov: 2206
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3. Učinki ozona v troposferi na navadno dobrovito (Viburnum lantana L.)Tomaž Remic, Helena Šircelj, Boris Turk, Franc Batič, 2002, izvirni znanstveni članek Ključne besede: bioindikacija, onesnaženost ozračja, vpliv na rastline, pigmenti, askorbinska kislina, navadna dobrovita, Viburnum lantana
Objavljeno v DiRROS: 12.07.2017; Ogledov: 6222; Prenosov: 2438
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4. Raziskave gozdnih tal in rizosfere ter njihov vpliv na nekatere fiziološke parametre gozdnega drevja v izbranih gozdnih ekosistemih, sestojnih tipih in razvojnih stadijih gozda : elaboratHojka Kraigher, Gregor Božič, Matjaž Čater, Miran Čas, Dušan Jurc, Maja Jurc, Polona Kalan, Lado Kutnar, Anton Kralj, Robert Robek, Primož Simončič, Igor Smolej, Mihej Urbančič, Matej Rupel, Jurij Diaci, Helena Šircelj, Tomaž Sinkovič, Cvetka Ribarič-Lasnik, Samar Al Sayegh Petkovšek, Julija Beričnik-Vrbovšek, Andrej Piltaver, Reinhard Agerer, Tadeja Trošt Sedej, Urša Vilhar, 1999, elaborat, predštudija, študija Ključne besede: gozdna tla, rizosfera, gozdno drevje, fiziološki parameter, raziskovalna ploskev, Pokljuka, Kočevska Reka, stres, vpliv na gozd
Objavljeno v DiRROS: 12.07.2017; Ogledov: 5283; Prenosov: 1560
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